The Universal Mobile Telecommunications System (UMTS) is a mainstream third generation (3G) radio communications standard formulated by the Third Generation Partnership Project (3GPP). To meet users' increasing rate requirements, a high speed packet access (HSPA) technology is introduced into the UMTS to improve spectrum efficiency.
The HSPA supports multiflow transmission (Multiflow) in a published Release 11 protocol, that is, a user equipment (UE) may receive downlink high speed downlink shared channels (HS-DSCH) from multiple cells at a cell edge. Scenarios supported by the protocol include single frequency dual cell (SF-DC), dual frequency dual cell (DF-DC), dual frequency triple cell (DF-3C), and dual frequency quad cell (DF-4C).
In an SF-DC scenario, a UE receives downlink data of two cells at a same frequency, where one cell is a serving cell (serving HS-DSCH cell), and the other cell is an assisting serving cell (assisting serving HS-DSCH cell). Correspondingly, the UE feeds back an ACK/CQI (acknowledgement/Channel Quality Indication) to each cell. On the 68th session of radio access network working group 1 (RAN 1), a consensus is reached: for an SF-DC, a UE uses one HS-DPCCH (high speed dedicated physical control channel) to provide a joint feedback to two cells, and the channel bears ACK/CQI information corresponding to a downlink.
For timing relationships between an HS-DPCCH and an uplink dedicated physical channel (DPCH), and between the HS-DPCCH and an HS-PDSCH (high speed physical downlink shared channel), concepts of a time reference cell and a non-time reference cell are introduced for Multiflow. The time reference cell (the time reference cell may be a serving cell, and may also be an assisting cell) is configured by a higher layer, and the timing relationships between an HS-DPCCH in the time reference cell and an uplink dedicated physical channel (DPCH), and between the HS-DPCCH and an HS-PDSCH are maintained the same as timing relationships in a case of non-Multiflow.
Currently, in the TS25.211 protocol, the only description is that a timing relationship of an HS-DPCCH in a time reference cell is obtained by calculating by using ΓDIFF, and there is no description about how to obtain a timing relationship of an HS-DPCCH in a non-time reference cell. By directly applying related stipulations of ΓDIFF, timing relationships between an HS-DPCCH in a non-time reference cell and an uplink DPCH, and between the HS-DPCCH and an HS-PDSCH are obtained or an error may occur.